Show simple item record

dc.contributor.authorBuder, Sven
dc.contributor.authorLind, Karin
dc.contributor.authorNess, Melissa K.
dc.contributor.authorFeuillet, Diane K.
dc.contributor.authorHorta, Danny
dc.contributor.authorMonty, Stephanie
dc.contributor.authorBuck, Tobias
dc.contributor.authorNordlander, Thomas
dc.contributor.authorBland-Hawthorn, Joss
dc.contributor.authorCasey, Andrew R.
dc.contributor.authorSilva, Gayandhi M. De
dc.contributor.authorD'Orazi, Valentina
dc.contributor.authorFreeman, Ken C.
dc.contributor.authorHayden, Michael R.
dc.contributor.authorKos, Janez
dc.contributor.authorMartell, Sarah L.
dc.contributor.authorLewis, Geraint F.
dc.contributor.authorLin, Jane
dc.contributor.authorSchlesinger, Katharine J.
dc.contributor.authorSharma, Sanjib
dc.contributor.authorSimpson, Jeffrey D.
dc.contributor.authorStello, Dennis
dc.contributor.authorZucker, Daniel B.
dc.contributor.authorZwitter, Tomaz
dc.contributor.authorCiuca, Ioana
dc.contributor.authorHorner, Jonathan
dc.contributor.authorKobayashi, Chiaki
dc.contributor.authorTing, Yuan-Sen
dc.contributor.authorWyse, Rosemary F. G.
dc.contributor.authorCollaboration, The GALAH
dc.date.accessioned2022-02-17T16:30:04Z
dc.date.available2022-02-17T16:30:04Z
dc.date.issued2022-02-01
dc.identifier.citationBuder , S , Lind , K , Ness , M K , Feuillet , D K , Horta , D , Monty , S , Buck , T , Nordlander , T , Bland-Hawthorn , J , Casey , A R , Silva , G M D , D'Orazi , V , Freeman , K C , Hayden , M R , Kos , J , Martell , S L , Lewis , G F , Lin , J , Schlesinger , K J , Sharma , S , Simpson , J D , Stello , D , Zucker , D B , Zwitter , T , Ciuca , I , Horner , J , Kobayashi , C , Ting , Y-S , Wyse , R F G & Collaboration , T GALAH 2022 , ' The GALAH Survey: Chemical tagging and chrono-chemodynamics of accreted halo stars with GALAH+ DR3 and $Gaia$ eDR3 ' , Monthly Notices of the Royal Astronomical Society , vol. 510 , no. 2 . https://doi.org/10.1093/mnras/stab3504
dc.identifier.issn0035-8711
dc.identifier.otherArXiv: http://arxiv.org/abs/2109.04059v2
dc.identifier.otherORCID: /0000-0002-4343-0487/work/108467532
dc.identifier.urihttp://hdl.handle.net/2299/25387
dc.description© 2021 The Author(s) Published by Oxford University Press on behalf of Royal Astronomical Society. This is the accepted manuscript version of an article which has been published in final form at https://doi.org/10.1093/mnras/stab3504
dc.description.abstractSince the advent of $Gaia$ astrometry, it is possible to identify massive accreted systems within the Galaxy through their unique dynamical signatures. One such system, $Gaia$-Sausage-Enceladus (GSE), appears to be an early "building block" given its virial mass $> 10^{10}\,\mathrm{M_\odot}$ at infall ($z\sim1-3$). In order to separate the progenitor population from the background stars, we investigate its chemical properties with up to 30 element abundances from the GALAH+ Survey Data Release 3 (DR3). To inform our choice of elements for purely chemically selecting accreted stars, we analyse 4164 stars with low-$\alpha$ abundances and halo kinematics. These are most different to the Milky Way stars for abundances of Mg, Si, Na, Al, Mn, Fe, Ni, and Cu. Based on the significance of abundance differences and detection rates, we apply Gaussian mixture models to various element abundance combinations. We find the most populated and least contaminated component, which we confirm to represent GSE, contains 1049 stars selected via [Na/Fe] vs. [Mg/Mn] in GALAH+ DR3. We provide tables of our selections and report the chrono-chemodynamical properties (age, chemistry, and dynamics). Through a previously reported clean dynamical selection of GSE stars, including $30 < \sqrt{J_R~/~\mathrm{kpc\,km\,s^{-1}}} < 55$, we can characterise an unprecedented 24 abundances of this structure with GALAH+ DR3. Our chemical selection allows us to prevent circular reasoning and characterise the dynamical properties of the GSE, for example mean $\sqrt{J_R~/~\mathrm{kpc\,km\,s^{-1}}} = 26_{-14}^{+9}$. We find only $(29\pm1)\%$ of the GSE stars within the clean dynamical selection region. Our methodology will improve future studies of accreted structures and their importance for the formation of the Milky Way.en
dc.format.extent29
dc.format.extent6994339
dc.language.isoeng
dc.relation.ispartofMonthly Notices of the Royal Astronomical Society
dc.subjectastro-ph.GA
dc.subjectastro-ph.SR
dc.titleThe GALAH Survey: Chemical tagging and chrono-chemodynamics of accreted halo stars with GALAH+ DR3 and $Gaia$ eDR3en
dc.contributor.institutionCentre for Astrophysics Research (CAR)
dc.contributor.institutionSchool of Physics, Engineering & Computer Science
dc.contributor.institutionDepartment of Physics, Astronomy and Mathematics
dc.description.statusPeer reviewed
rioxxterms.versionofrecord10.1093/mnras/stab3504
rioxxterms.typeJournal Article/Review
herts.preservation.rarelyaccessedtrue


Files in this item

Thumbnail

This item appears in the following Collection(s)

Show simple item record